1. Field of the Invention
Embodiments relate to an organic light emitting diode (OLED) display and a method of manufacturing the same. More particularly, embodiments relate to an OLED display that may be less susceptible to deterioration of electrical characteristics due to ultraviolet (UV) radiation than conventional displays, and a method of manufacturing the same.
2. Description of the Related Art
In general, organic light emitting diode (OLED) displays exhibit self-emission characteristics, i.e., self-luminous, and have higher performance in terms of wider viewing angle, higher brightness and contrast, near instantaneous response speed, and low power consumption with thin and compact form factor over liquid crystal displays (LCDs).
An OLED display includes a plurality of OLEDs coupled between a matrix of scan lines and data lines to form a plurality of pixels. An OLED includes an anode electrode, a cathode electrode, and an organic thin film layer formed between the anode electrode and the cathode electrode. An OLED further includes a hole transport layer, an organic light emitting layer, and an electron transport layer. If a given voltage is applied to the anode electrode and the cathode electrode, the holes injected through the anode electrode and the electrons injected through the cathode electrode are re-coupled with each other in the organic light emitting layer. As a result, light is emitted due to a difference in energy.
Since OLED displays include organic materials, OLED displays are vulnerable to attack by hydrogen or oxygen. Additionally, since the cathode electrode is made of a metal material, the cathode electrode may be easily oxidized by moisture in the air which leads to deterioration in electrical and light emitting characteristics. In order to prevent electrical and light emitting characteristics from deteriorating, a can or cup shaped container made of a metal material, or a sealing substrate made of glass or plastic is typically provided on a substrate on which the OLED may be formed. The container or sealing substrate and substrate are then sealed via a sealant such as epoxy-based sealants.
It is difficult, however, to apply such a configuration to a thin or flexible OLED display. Accordingly, in order to seal a thin or flexible OLED display, a thin film encapsulation technology may be employed. Ultraviolet (UV) radiation is typically used in employing thin film encapsulation technology to form OLED displays. If UV radiation is irradiated onto the organic thin film layer, however, thermal damage is generated. Such thermal damage negatively affects and changes the characteristics of the organic thin film layer, and surface characteristics between the organic thin film layer and the cathode electrode are also negatively affected. Accordingly, there remains a need to address one or more of these drawbacks and disadvantages of the related art.